Quick guide to Dilantin

Brand Name(s): Dilantin, Dilantin Kapseals, Phenytek

Generic Name Phenytoin

What are phenytoin capsules and extended-release capsules?

PHENYTOIN (Dilantin® Kapseals®, Phenytek™) helps to control seizures (convulsions) in certain types of epilepsy. Phenytoin can help to prevent seizures occurring during or after surgery. Phenytoin also treats nerve-related pain such as trigeminal neuralgia. It is not for common aches and pains. Generic phenytoin capsules are available.

What should my health care professional know before I take phenytoin?

They need to know if you have any of these conditions:

an alcohol abuse problem

blood disorders or disease

diabetes

fever

heart problems

kidney disease

liver disease

porphyria

receiving intramuscular injections

receiving radiation therapy

skin problems

thyroid disease

an unusual or allergic reaction to phenytoin, other medicines, foods, dyes, or preservatives

pregnant or trying to get pregnant

breast-feeding

How should I take this medicine?

Take phenytoin capsules by mouth. Follow the directions on the prescription label. Swallow the capsules with a drink of water. If you are taking extended-release capsules, swallow them whole; do not crush or chew. Take phenytoin with food if it upsets your stomach. It may be best to take your phenytoin capsules consistently with or without food. Take your doses at regular intervals. Do not take your medicine more often than directed.

What if I miss a dose?

Try not to miss a scheduled dosage, especially if you are taking phenytoin extended-release capsules just once per day. If you miss a dose, take it as soon as you can. If it is less than four hours to your next dose, take only that dose. If you only take a dose once a day and do not remember until the next day, skip the missed dose and resume your normal schedule. Do not take double or extra doses.

What drug(s) may interact with phenytoin?

Many medicines can interact with phenytoin; check with your prescriber or health care professional if you regularly take other medications or over-the-counter products. Some of the medicines that can interact with phenytoin are listed:

Tell your prescriber or health care professional about all other medicines you are taking, including non-prescription medicines. Also tell your prescriber or health care professional if you are a frequent user of drinks with caffeine or alcohol, if you smoke, or if you use illegal drugs. These may affect the way your medicine works. Check with your health care professional before stopping or starting any of your medicines.

What side effects may I notice from taking phenytoin?

Side effects that you should report to your prescriber or health care professional as soon as possible:

chest pain or tightness; fast or irregular heartbeat (palpitations)

confusion, nervousness, hostility, or other behavioral changes (especially in children or elderly patients)

dark yellow or brown urine

difficulty breathing, wheezing or shortness of breath

double vision or uncontrollable and rapid eye movement

fainting spells or lightheadedness

fever, sore throat

headache

loss of seizure control

mouth ulcers

poor control of body movements or difficulty walking

redness, blistering, peeling or loosening of the skin, including inside the mouth

sexual problems (painful erections, loss of sexual desire)

skin rash, itching

stomach pain

swollen or painful glands

unusual bleeding or bruising, pinpoint red spots on skin

unusual tiredness or weakness

unusual swelling

vomiting

yellowing of the eyes or skin

Side effects that usually do not require medical attention (report to your prescriber or health care professional if they continue or are bothersome):

If you take phenytoin for seizures, it is a good idea to carry an identification card, necklace or bracelet with details of your condition, medications and prescriber or health care professional.

Do not change brands or dosage forms of phenytoin without discussing the change with your prescriber or health care professional.

You may feel dizzy or drowsy. Do not drive, use machinery, or do anything that needs mental alertness until you know how phenytoin affects you. To reduce the risk of dizzy or fainting spells, do not sit or stand up quickly, especially if you are an older patient. Alcohol can make you more dizzy, increase flushing and rapid heartbeats. Avoid alcoholic drinks.

If you are going to have surgery, tell your prescriber or health care professional that you are taking phenytoin.

Birth control pills (contraceptive pills) may not work properly while you are taking phenytoin; talk with your prescriber about the use of other methods of birth control.

Phenytoin can cause unusual growth of gum tissues; visit your dentist regularly. Problems can arise if you need dental work, and in the day to day care of your teeth. Try to avoid damage to your teeth and gums when you brush or floss your teeth.

Do not take antacids at the same time as phenytoin. If you get an upset stomach and want to take an antacid or medicine for diarrhea, make sure there is an interval of 2 to 3 hours before or after you took phenytoin.

Where can I keep my medicine?

Keep out of the reach of children in a container that small children cannot open.

(Note: The above information is not intended to replace the advice of your physician, pharmacist, or other healthcare professional. It is not meant to indicate that the use of the product is safe, appropriate, or effective for you.)